There are two protective requirements for optical fibers in formation of the fiber optic cables
: one is less stress on optical fibers; the other is waterproof of optical fibers.
The outermost layer of the cable is a plastic sheath, and the inside is a metal sheath, and more inside is a water-blocking layer expanded by water. The core of the cable is pasted together with the optical fiber. Fiber optic has four waterproof gates, namely, plastic sheath, metal sheath, water-proof layer and ointment. Then the question arises. Why are optical fibers so afraid of water? Why aren't the aquarium glass and window glass at home afraid of water while they are waterproof? Why are they all glass so different?
It is generally believed that optical fibers are not afraid of water, because glass has excellent water absorption. It is generally believed that optical fibers are not afraid of water, because glass has excellent water absorption. But in fact, water is very harmful to cables. If water enters the fiber optic cable, it will damage the optical fiber if it freezes and expands in the cold water, so the cable needs to be filled with ointment to prevent moisture from entering.
The reason why optical fibers
are afraid of water is that optical fibers are made up of glass (Si04) tetrahedrons connected with each other. In a Si-O-Si network, oxygen atoms exist in the form of bridge oxygen. However, in the environment with water, after the glass surface adsorbs water and gas, the hydrolysis reaction slowly occurs, which leads to the breakage of the silicon-oxygen bond in the original network-Si-10-Si-1 and the transformation of bridge oxygen into non-bridge oxygen. As a result, the glass cracks are caused, which are growing continuously.
Whether for fish tank glass, window glass or optical fiber glass, they are afraid of water. The difference is that fish tank glass, window glass are very thick, with the thickness of 3mm, 5mm, l0mm, even if there are 0.05mm cracks do not affect the strength of the glass, and naked eyes can not see changes. Fiber optic glass is different. The diameter of fiber optic glass is only 0.125 mm, which is as thin as hair. If there is an 0.05 mm crack, the diameter of fiber optic will remain 0.075 mm. Therefore, fiber optic is very easy to break. In addition, the appearance of OH root will increase the absorption loss of fiber to light. This is why aquarium glass and window glass are not afraid of water while optical fiber glass is afraid of water.
Even so, the cable is damaged, and the joint box is not sealed properly, and the exposure of bare fibers will lead to shorter service life and natural fiber breakage due to water.
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provides high quality optical cables, which is the best choice for buying fiber optic cable